Illuminating the Heart--and Helping it to Beat

The treatment is familiar to anyone who’s watched a medical drama: A person’s heart stops beating, and caregivers use a defibrillator to deliver an electric shock to bring it back.

But the electricity can cause tissue damage and pain. So, a team at Johns Hopkins is investigating how they might replace electricity with light. This involves the field of optogenetics, which is only about a decade old.

The idea is that light-responsive proteins called opsins will be inserted into cells. When exposed to light, these proteins become allow an electric charge to come through. Scientists envision the opsins being inserted ahead of time in people with arrhythmia, which is an irregular heartbeat, and then being activated when needed. Right now, this is being done virtually—on a heart that "beats" inside a computer.

We talk with Natalia Trayanova, the Murray B. Sachs Professor of Biomedical Engineering at Johns Hopkins, and Patrick Boyle, a postdoctoral fellow in the lab. Their research was published in the journal Nature Communications last month.